A large study on 81 DMD and BMD patients with mutations either affecting all dystrophin gene products (54 patients) or all products except Dp71 (27 patients) found that the BMD patients with intellectual disability had mutations affecting Dp71 expression and that mutations upstream of exon 62 in DMD patients are associated with normal to borderline cognitive performance [6]. The gene discussed is DMD; the disease is Becker muscular dystrophy.